Ah I get what you mean. However you could calculate it as (@Strength+@Enlarge)*1.5 as well. But true in this case it's actually wanted that way. I thought you were refering to something else, that would be separately rounded. I honestly can't think of an example right now. Power Attack gets a 1.5x bonus (over onehand) when used twohanded (in PF at least) but it's base values are so that it always results in a full number. However let's say for sake of arguments that that wasn't the case and it could result in a value like 4.5 (or that there is actually something like that), which would normally be rounded to 4. Now the Strength results in another 4.5 after the multiplier, also rounded to 4, which means calculated correctly the result is 8. Roll20 will mark it as 9 however and since that looks like correct number it's not as obvious that it's twice wrong actually. Well anyway, for most applications it will be enough to simply ignore a .5 at the end and if you only have a single *1.5 in the macro that is a reliable method. If you have multiple though, you should be more careful.